1. Spatially Graded Graphitization on 4H-SiC (0001) with Si-Sublimation Gradient for High Quality Epitaxial Graphene Growth
- Author
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Naoto Tamai, Noboru Ohtani, Yasunori Kutsuma, Arata Yoshii, Shoji Ushio, and Tadaaki Kaneko
- Subjects
Materials science ,Scanning electron microscope ,business.industry ,Graphene ,Mechanical Engineering ,Nanotechnology ,Raman mapping ,Condensed Matter Physics ,law.invention ,symbols.namesake ,Mechanics of Materials ,law ,symbols ,Optoelectronics ,General Materials Science ,Sublimation (phase transition) ,Epitaxial graphene ,Raman spectroscopy ,business - Abstract
We report a new approach to produce high quality epitaxial graphene based on the concept of controlling Si sublimation rate from SiC surface. By putting a mask substrate to suppress Si sublimation from the SiC surface in ultrahigh vacuum, epitaxial graphene growth at 4H-SiC (0001) was locally controlled. Spatially graded surface graphitization was confirmed in a scanning electron microscopy contrast from the outside unmasked region to the inside masked region. The contrast was discussed with Raman characterization as the increase of graphene thickness and the surface compositional change of SiC. Results indicate two types of growth processes of epitaxial graphene at 4H-SiC (0001) step-terrace structures.
- Published
- 2012